linux-kernel - Re: oops/warning report for the week of November 26, 2008

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <200811270902.18020.jbarnes@virtuousgeek.org>
Date:	Thu, 27 Nov 2008 09:02:12 -0800
From:	Jesse Barnes <jbarnes@...tuousgeek.org>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	Arjan van de Ven <arjan@...ux.intel.com>,
	Yinghai Lu <yinghai@...nel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	NetDev <netdev@...r.kernel.org>, x86@...nel.org,
	Andrew Morton <akpm@...ux-foundation.org>,
	"Theodore Ts'o" <tytso@....edu>,
	Alan Cox <alan@...rguk.ukuu.org.uk>
Subject: Re: oops/warning report for the week of November 26, 2008

On Thursday, November 27, 2008 3:52 am Ingo Molnar wrote:
> * Arjan van de Ven <arjan@...ux.intel.com> wrote:
> > Rank 8: mtrr_trim_uncached_memory (warning)
> > 	Reported 227 times (619 total reports)
> > 	There is a high number of machines where our MTRR checks
> > 	trigger. I suspect we are too picky in accepting the MTRR
> > 	configuration.
>
> the warning here means: "the BIOS messed up but we fixed it up for
> you just fine".
>
> Should we print a DMI descriptor so that it can be tracked back to the
> bad BIOSen in question? Or should we (partially) silence the warning
> itself? Those BIOS bugs need fixing really: older kernels will boot up
> with bad MTRR settings - resulting in a super-slow system or other
> weirdnesses. We can tone down the message so that it doesnt show up in
> kerneloops.org. It's up to you.

I actually think we're doing something wrong here, since so many platforms 
have this behavior.  It's likely that there's an undocumented, additional 
check needed to determine whether a slot is hot pluggable.  Matthew Garrett 
recently posted a patch to check for ACPI _RMV methods, which should be an 
improvement.  I'll be putting that into linux-next soon for testing.

-- 
Jesse Barnes, Intel Open Source Technology Center

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/